What type of refrigerant is typically used in residential units?

R-410A is commonly used in residential air conditioning systems due to its efficiency and lower environmental impact compared to other refrigerants. It is a hydrofluorocarbon (HFC) that does not deplete the ozone layer, making it a more environmentally friendly option when considering global warming potential.

Since 2010, R-410A has largely replaced R-22 in new residential systems as R-22 production is being phased out due to its ozone-depleting properties. R-410A operates at a higher pressure than R-22, which enhances the efficiency of cooling systems. This characteristic allows air conditioning units designed for R-410A to achieve better performance in terms of cooling output and energy consumption.

While R-134A and R-404A are used in other applications, such as automotive and commercial refrigeration respectively, they are not standard in residential air conditioning systems. R-134A was also commonly used in older refrigeration systems but has not gained the same traction in residential air conditioning as R-410A has.